Welding power to auxiliary power conversion system and method

ABSTRACT

Methods and systems for manufacturing and using the auxiliary power conversion unit, which is capable of being remotely located from a welding power supply unit during a welding operation, are provided. In some embodiments, the auxiliary power conversion is capable of outputting DC as well as AC power, capable of outputting multiple voltages consistent with the demands of typical auxiliary tools, such as a hand grinder or a light. In certain embodiments, the power conversion unit may be a stand-alone system or may be incorporated into a device, such as a wire feeder, which is configured to derive power from the arc potential. The power conversion unit may contain control and processing electronics that may include a controller, a processor, memory, and so forth.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a Continuation Application of U.S. patent application Ser. No.12/488,143, entitled “Welding Power to Auxiliary Power Conversion Systemand Method”, filed Jun. 19, 2009, which is a Non-Provisional Applicationof Provisional Application No. 61/145,341, entitled “Weld Voltage toAuxiliary Power Converter for Tools”, filed Jan. 16, 2009, both of whichare herein incorporated by reference.

BACKGROUND

The present disclosure relates generally to welding power sources, andmore particularly, to systems and methods for providing auxiliary powerat the location of the weld.

Welding is a process that has increasingly become ubiquitous in allindustries. While such processes may be automated in certain contexts, alarge number of applications continue to exist for manual weldingoperations. While the power requirements of the weld creation processremain central to a manual welding operation, additional auxiliary powerrequirements may also be necessary for weld joint preparation and cleanup. For instance, lights, hand grinders, torch cooler pumps, and soforth, may require an additional 115V or 230V AC output.

Some welding power sources provide auxiliary AC outlets to meet thisdemand. However, the welding power source may be located far from thelocation of the weld creation. It is now recognized that this mayinconveniently necessitate the use of extension cords that carry theauxiliary power from the welding power source to the location of theweld creation. It is now recognized that these extension cordscontribute to power losses since the power may be transferred longdistances. Additionally, since these extension cords terminate in thesame general location as the weld cables used to power the weld creationprocess, it is now recognized that they contribute to cable clutter inand around the weld area. Further, inefficiencies may result from theuse of such cables due to misplacement, borrowing, and theft of theextension cables.

BRIEF DESCRIPTION

The present disclosure is directed to systems and methods relating to anauxiliary power conversion unit for use in a welding system. In someembodiments, the auxiliary power conversion unit is capable ofoutputting DC as well as AC power and is capable of outputting multiplevoltages consistent with the demands of typical auxiliary tools, such asa hand grinder, a light, and so forth. In particular, the presentdisclosure provides methods and systems for manufacturing and using theauxiliary power conversion unit, which is capable of being remotelylocated from a welding power supply unit during a welding operation. Thepower conversion unit is capable of drawing power from an arc potentialvia an electrode cable and a work cable and is sufficiently portable tofacilitate easy replacement or transfer between welding systems. Incertain embodiments, the power conversion unit may be a stand-alonesystem or may be incorporated into a device, such as a wire feeder,which is configured to derive power from the arc potential. In someembodiments, the power conversion unit may include an interface thatincludes a display panel configured to display operating parameters,such as the level of power output, the mode of operation, and so forth,to the user. The power conversion unit may contain control andprocessing electronics that may include a controller, a processor,memory, and so forth.

DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 illustrates an exemplary welding power supply where a powerconversion unit is located along an electrode cable in accordance withaspects of the present disclosure;

FIG. 2 illustrates an exemplary welding power supply where a powerconversion unit is located along an electrode cable and a lead cable inaccordance with aspects of the present disclosure;

FIG. 3 illustrates an exemplary welding power supply where a powerconversion unit connects to an electrode cable via an supplemental cablein accordance with aspects of the present disclosure;

FIG. 4 illustrates an exemplary welding power supply where a powerconversion unit connects to an electrode cable via an supplemental cableand to a lead cable in accordance with aspects of the presentdisclosure;

FIG. 5 illustrates an exemplary welding power supply where a powerconversion unit is located inside a wire feeder in accordance withaspects of the present disclosure;

FIG. 6 illustrates an exemplary welding power supply where a powerconversion unit is located inside a wire feeder and connects to a leadcable in accordance with aspects of the present disclosure;

FIG. 7 illustrates an exemplary stand-alone power conversion unit inaccordance with aspects of the present disclosure;

FIG. 8 is a block diagram illustrating exemplary internal components ofa power conversion unit in accordance with aspects of the presentdisclosure;

FIG. 9 is a block diagram of an exemplary controller that may be used tocontrol the operation of a welding power source and a power conversionunit in accordance with aspects of the present disclosure;

FIG. 10 illustrates an exemplary method of manufacturing the exemplarywelding power supply system of FIG. 1 in accordance with aspects of thepresent disclosure; and

FIG. 11 illustrates an exemplary method of manufacturing the exemplarywelding power supply system of FIG. 3 in accordance with aspects of thepresent disclosure.

DETAILED DESCRIPTION

As discussed in further detail below, various embodiments of anauxiliary power conversion unit for use in a welding system are providedin accordance with present embodiments. The auxiliary power conversionunit is electronic, capable of outputting DC as well as AC power, andcapable of outputting multiple voltages (e.g. 115V, 230V, etc.)consistent with the demands of typical auxiliary tools (e.g. handgrinder, light, etc.). The auxiliary power conversion unit is alsocapable of being remotely located from a welding power supply unitduring a welding operation. The power conversion unit is capable ofdrawing power from an arc potential via an electrode cable and a workcable and is sufficiently portable to facilitate easy replacement ortransfer between welding systems. Furthermore, the power conversion unitmay be a stand-alone system or may be incorporated into a device, suchas a wire feeder, which is configured to derive power from the arcpotential.

The power conversion unit may include an interface that includes adisplay panel configured to display operating parameters, such as thelevel of power output, the mode of operation, and so forth, to the user.Additionally, the interface may include a power switch and visualindicators of system parameters, such as the power state of the system,temperature overload, and so forth. The power conversion unit maycontain control and processing electronics that may include acontroller, a processor, memory and so forth. The memory may includevolatile or non-volatile memory, such as read only memory (ROM), randomaccess memory (RAM), magnetic storage memory, optical storage memory, ora combination thereof. Furthermore, control parameters may be stored inthe memory along with code configured to provide a specific output (e.g.increase/decrease power supply output based on the auxiliary loaddemands).

Turning now to the drawings, FIG. 1 illustrates an exemplary weldingpower supply 10, which functions to power, control and provideconsumables to a welding operation and auxiliary equipment in accordancewith aspects of the present disclosure. An interface panel 12 on thefront side of the power supply unit 10 in the illustrated embodimentcontains a control panel 14, through which a user may control the supplyof materials, such as power, gas flow, and so forth, to a weldingoperation, via switches 16, knobs 18, and so forth. In some embodiments,the power supply unit 10 may be communicatively coupled to additionalsystem components, such as a wall power outlet, a battery, engine-drivenpower sources, and so forth. An electrode assembly 19 extends from thepower supply unit 10 to a remote location where a weld may take place. Afirst cable 20 and a welding electrode 22 couple to the power supplyunit 10 as components of an electrode assembly 23. The electrodeassembly 23 extends from the power supply unit 10 to a remote locationwhere a weld may take place. It should be noted that the electrode 22may be an electrode suitable for a variety of welding processes. Forinstance, the electrode 22 may be a torch suitable for metal inert gas(MIG) operations, a stinger suitable for stick welding operations, andso forth.

A second cable 24 connects a work lead clamp 26 to the power supply unit10. During operation, the work lead clamp 26 typically connects to aworkpiece to close the circuit between the electrode 22, the work piece,and the supply unit 10, and to ensure proper current flow. In theillustrated embodiment, an exemplary auxiliary power conversion unit 28,which derives power from the arc potential and converts this power to anoutput suitable for auxiliary load requirements, is positioned along thelength of the first cable 20 as an integral feature of the cable 20.Since the power conversion unit 28 is connected to the first cable 20,the unit 28 may be remotely located from the power supply unit 10, whichenables the power conversion unit 28 to be located in close proximity toa weld without the use of extension cords. A third cable 30 connects aclamp 32 to the power conversion unit 28. During operation, the clamp 32typically connects to the workpiece to place the power conversion unit28 across the welding output, allowing it to derive power from the arcpotential. Auxiliary equipment, such as a light 34, may plug into thepower conversion unit 28 and extend to the location of its use via anadditional cable 36.

FIGS. 2-6 illustrate alternative placements of the power conversion unit28 with respect to the power supply unit 10 and the electrode 22. FIG. 2illustrates a further embodiment of the configuration shown in FIG. 1.In the embodiment illustrated in FIG. 2, the work lead clamp 26 may beeliminated with respect to FIG. 1. The second cable 24 may then beconnected to the auxiliary power conversion unit 28. In the illustratedembodiment, two cables 20 and 24, are used to connect the auxiliarypower conversion unit 28 to the power supply unit 10. However, infurther embodiments, a single supply cable (not shown) may connect theauxiliary power conversion unit 28 to the power supply unit 10. In suchan embodiment, the single supply cable would still include at least twoconductors such that both internal components of the first cable 20 andinternal components of the second cable 24 would still be connected tothe auxiliary power conversion unit 28.

In the embodiment illustrated in FIG. 3, an electrode assembly 38 andthe work lead assembly 23 extend from the power supply unit 10 to aremote location where a weld may take place. The power conversion unit28 is connected to the first cable 20 via a fourth cable 50, whichbranches off from the first cable 20. During operation, the work leadclamp 26 and the clamp 32 connect to the workpiece. During operation,the work lead clamp 26 closes the circuit between the electrode 22, thework piece, and the supply unit 10, and ensures proper current flow. Theclamp 32 places the power conversion unit 28 across the welding output,allowing it to derive power from the arc potential. Auxiliary equipment,such as lights, hand grinders, and so forth, may plug into the powerconversion unit 28 and extend to the location of their use viaadditional cables such as the cables that are provided as features ofthe auxiliary equipment. FIG. 4 illustrates a further embodiment of theconfiguration shown in FIG. 3. In the embodiment illustrated in FIG. 4,the work lead clamp 26 may be eliminated with respect to FIG. 3. In thisembodiment, the second cable 24 may then be connected to the auxiliarypower conversion unit 28.

In the embodiment illustrated in FIG. 5, the work lead clamp 26 is stillconnected to the power supply unit 10 via the second cable 24 withrespect to FIGS. 1 and 3. However, a cable 60 connects a wire feeder,which feeds electrode wire to the welding operation, to the power supplyunit 10. An additional cable 64 connects the wire feeder 62 to thewelding electrode 22. In this embodiment, the power conversion unit 28is located inside the wire feeder 62 and the clamp 32 connects to thewire feeder 62 via its cable 30. During operation, the clamp 32 connectsto the workpiece to place both the wire feeder 62 and the powerconversion unit 28 across the arc potential. In other embodiments, thepower conversion unit 28 may be placed in other equipment as long as aconnection exits such that the equipment is located across the arcpotential to enable it to derive power. The illustrated embodiment mayallow for less clutter around the weld compared to traditional systems,since the unit 28 is incorporated into a preexisting system component.

FIG. 6 illustrates a further embodiment of the configuration shown inFIG. 5. In the embodiment illustrated in FIG. 6, the work lead clamp 26may be eliminated with respect to FIG. 5. The second cable 24 may thenbe connected to the auxiliary power conversion unit 28. In theillustrated embodiment, the two cables 60 and 24, are used to connectthe auxiliary power conversion unit 28 to the power supply unit 10.However, in further embodiments, a single supply cable (not shown) mayconnect the auxiliary power conversion unit 28 to the power supply unit10. In such an embodiment, the single supply cable would still includeat least two conductors such that both internal components of the firstcable 60 and internal components of the second cable 24 would still beconnected to the auxiliary power conversion unit 28.

FIG. 7 illustrates the stand-alone version of the power conversion unit28. The power conversion unit 28 may contain a front panel 70 thatincludes a user interface, through which the user may control theoperation of the unit 28. A display panel 72 is configured to displayoperating parameters, such as the level of power output, the mode ofoperation, and so forth, to the user during operation. A switch 74allows the user to power the unit 28 on and off. An indicator panel 76includes indicators 78 that may indicate to the user that the unit 28 ispowered on, overheating, and so forth. In the illustrated stand-aloneembodiment, the clamp 32 communicatively attaches to the unit via thefront panel 70 of the power conversion unit 28 to allow the unit 28 tobe placed across the arc potential. In the illustrated embodiment, thefront panel 70 includes a panel 79 that contains outlets 80 forauxiliary equipment that runs off of an 115V AC output and another panel82 that contains outlets 84 for auxiliary equipment that runs off a 230VAC output. In other embodiments, more or less panels with more or lessoutlets than illustrated may be included on the front panel 70. Forinstance, outlets that output other voltages consistent with therequirements of additional auxiliary equipment may be included.Additionally, panels that include outlets which output DC voltages maybe included. In certain embodiments, an exemplary front panel 70 mayinclude outlets for both AC and DC voltage outputs.

FIG. 8 is a block diagram illustrating the internal components of thepower conversion unit 28 and how they interface with the welding powersource 10 and a weld creation process 90. The welding power source 10may be a constant voltage or constant current source. Typically, theoutput of the power source 10 will be a low voltage (e.g. 40-50V), highcurrent (e.g. 1000 A) waveform that is consistent with the demands ofthe weld creation process 90. However, the power requirements at anauxiliary load 92, such as a drill or a hand grinder, will typicallynecessitate a high voltage (e.g. 115V, 165V, 230V, etc.), low current(e.g. 12 A, 16 A, 20 A, etc.) output. To achieve the power requirementsat an auxiliary load 92, an input power conversion stage, as representedby block 94, may be included in the power conversion unit 28. In certainembodiments, the input power conversion stage 94 may consist of twoconversion steps. The first step may include a boost converter, whichboosts the low voltage output of the welding power source 10 to a highervoltage more suitable for the requirements at the auxiliary load 92. Thesecond step may include a DC to AC inverter. In other embodiments, theinput power conversion stage 94 only includes the DC to AC inverter,which is used to allow power transmission to the next stage, the inputto output isolation stage, as represented by block 96.

The input to output isolation stage 96 may include a transformer, suchas a high-frequency ferrite-based transformer, which isolates anauxiliary circuit from a welding power circuit. In other embodiment, theinput to output isolation stage 96 may include other devices, such as aswitched or charge pumped capacitor network, a coupled magnetic device,and so forth. The isolation stage 96 is used to keep the auxiliarycircuit at a potential distinct from a potential of the welding powersupply 10. The output of the isolation stage 96 may be received by anoutput power conversion stage, as represented by block 98. Duringoperation, the output power conversion stage 98 converts the output ofthe isolation stage 96 to the waveform used at the auxiliary load 92.For instance, if the auxiliary load 92 requires a DC voltage output, theconversion stage 98 may include a rectifier and a filter to change thehigh frequency AC voltage on the secondary winding of the transformer inthe isolation stage 96 back to a DC voltage. If the auxiliary load 92requires a modified or true sine wave AC output, then the conversionstage 98 may include the rectifier and a half-bridge or full-bridgeinverter that shape the output wave. In some embodiments, the auxiliaryload 92 may require an approximately 50 or 60 Hz waveform.

It should be noted that the illustrated stages may be combined oreliminated based on the requirements at the auxiliary load 92. Further,certain stages may be performed in addition to the three illustratedcentral stages. For instance, an energy storage device (e.g. a battery),as represented by block 100, may be included in the power conversionunit 28. The inclusion of the energy storage device 100 may be a way tomitigate transient load requirements by providing all or some of thepower needed at the auxiliary load 92 during peak periods. The energystorage device 100 may then recharge from the welding power source 10 orfrom various outputs in the auxiliary storage device 19 duringsteady-state operation. This may be particularly useful when usingauxiliary loads 92 that may require high transient peak outputrequirements but low average requirements. Additionally, the energystorage device, as represented by block 100, may allow for delivery ofpower to auxiliary loads 92 at levels that exceed the maximum amount ofexcess energy supplied by the power supply 10.

The power conversion unit 28 may include circuitry that providesfeedback 102 to the welding power source 10. This feedback 102 maycommunicate a need for the welding power source 10 to increase voltageoutput when a level of auxiliary power needed is greater than that whichis needed for the welding operation. For instance, consider a constantcurrent power supply 10 being used for stick welding. If the powersupply 10 was set to 80 A for a ⅛″ E6010-5P electrode, the averageoutput power would be in the range from 2000-2400 Watts. However, atypical auxiliary load 92, such as an 8″ large hand grinder or a smalltorch cooler pump, may transiently require more than 2000-2400 Watts toproperly start. The feedback 102 would be necessary in this situation tocommunicate the additional power need of the auxiliary load 92 to thepower supply 10.

FIG. 9 illustrates an exemplary controller 110 that may be used tocontrol the circuitry in the welding power source 10 and the powerconversion unit 28. The controller includes a welding power sourcecontroller, as represented by block 112, which compiles inputs relatingto the power source output and power demands and outputs an appropriatecontrol signal 114. The welding power source controller 112 receivesfeedback from the location of the welding electrode, as represented byblock 116, regarding the power demands at the welding operation.Additionally, the power source controller 112 receives feedback from thepower conversion unit 28, as represented by block 118, regarding thepower requirements at the auxiliary load 92. The controller 110 alsoincludes a power conversion unit controller, as represented by block120, which compiles inputs relating to the auxiliary load 92 powerrequirements and outputs an appropriate control signal 122. The powerconversion unit controller 120 receives feedback from the auxiliary load92, as represented by block 124. For instance, the controller 120 mayreceive feedback indicating that a transient increase in voltage isneeded to start a tool. Additionally, the power conversion unit 28controller 120 may receive feedback from the power source 10 such asvoltage or current sensor information that indicates how much power isbeing output by the power source 10. A processor 128 receives thecontrol signals 114, 122, processes information from the control signals114, 122 and outputs a control signal 130 that modulates the powersupply 10 output, as represented by block 132, and a control signal 134that modulates the output of the power conversion unit 28, asrepresented by block 136.

FIGS. 10 and 11 illustrate methods of manufacturing the embodiments ofthe present disclosure illustrated in FIGS. 1 and 3, respectively. Theprocess of manufacturing the embodiment illustrated in FIG. 1 beginswith manufacturing the power supply unit 10, as represented by block 140in FIG. 10. First, the power supply base may be manufactured, asrepresented by block 142. Subsequently, a first port is provided in thebase, as represented by block 144, and a second port is manufactured inthe base, as represented by block 146. After the power supply unit 10has been manufactured (i.e. block 140 is complete), the work leadassembly 23 is manufactured, as represented by block 148. Subsequently,the clamp assembly 30, 32 is manufactured, as represented by block 150.Next, the electrode assembly 19 is manufactured, as represented by block152. First, the power conversion unit 28 is manufactured, as representedby block 154. Next, the electrode 22 is manufactured, as represented byblock 156, and the cable 20 that connects the electrode 22 to the powersupply unit 10 and the power conversion unit 28 is manufactured, asrepresented by block 158. After the electrode assembly 19 has beenmanufactured (i.e. block 152 is complete), the electrode assembly 19 isthen assembled, as represented by block 160. Finally, the componentsmanufactured in blocks 140, 148, 150 and 152 may be assembled, asrepresented by block 162. In other embodiments, the componentsmanufactured in blocks 140, 148, 150 and 152 may remain unassembleduntil use.

The process of manufacturing the embodiment illustrated in FIG. 3 beginswith manufacturing the power supply unit 10, as represented by block 140in FIG. 11. First, the power supply base may be manufactured, asrepresented by block 142. Subsequently, a first port is provided in thebase, as represented by block 144, and a second port is also provided inthe base, as represented by block 146. After the power supply unit 10has been manufactured (i.e. block 140 is complete), the work leadassembly 23 is manufactured, as represented by block 148. Subsequently,the clamp assembly 30, 32 is manufactured, as represented by block 150.Next, the electrode assembly 38 is manufactured, as represented by block164. First, the power conversion unit 28 is manufactured, as representedby block 166, and the cable 50 that connects the unit 28 to theelectrode cable 20 is manufactured, as represented by block 168. Next,the electrode 22 is manufactured, as represented by block 156, and thecable 20 that connects the electrode 22 to the power supply unit 10 ismanufactured, as represented by block 158. After the electrode assembly19 has been manufactured (i.e. block 164 is complete), the electrodeassembly 38 is then assembled, as represented by block 170. Finally, thecomponents manufactured in blocks 140, 148, 150 and 164 may beassembled, as represented by block 172. In other embodiments, thecomponents manufactured in blocks 140, 148, 150 and 164 may remainunassembled until use.

While only certain features of the present disclosure have beenillustrated and described herein, many modifications and changes willoccur to those skilled in the art. It is, therefore, to be understoodthat the appended claims are intended to cover all such modificationsand changes as fall within the true spirit of the present disclosure.

The invention claimed is:
 1. An auxiliary power conversion device,comprising: an input power converter capable of receiving an inputvoltage from a welding power supply unit connected to the auxiliarypower conversion device, wherein the input power converter is capable ofconverting the input voltage received from the welding power supply unitto a first alternating current (AC) output; an input-to-output isolationcircuit, wherein the input-to-output isolation circuit is capable ofreceiving the first AC output and maintaining an auxiliary load at adifferent potential than the welding power supply unit, wherein theinput-to-output isolation circuit is configured to transform the firstAC output to a second AC output; and an output power converter capableof converting the second AC output to a desired frequency and a desiredwaveform for the auxiliary load.
 2. The auxiliary power conversiondevice of claim 1, wherein the input power converter is a boostconverter capable of boosting the input voltage from the welding powersupply unit to the first AC output having a higher voltage than theinput voltage.
 3. The auxiliary power conversion device of claim 1,wherein the desired frequency is approximately 50 Hz or approximately 60Hz.
 4. The auxiliary power conversion device of claim 1, comprising anenergy storage module configured to be charged by the first AC output,the second AC output, or the input voltage when a demand level from theauxiliary load is less than a supply level of the second AC output. 5.The auxiliary power conversion device of claim 4, wherein the energystorage module comprises a storage device that provides power duringtransient auxiliary load events.
 6. The auxiliary power conversiondevice of claim 1, comprising an energy storage module that is rechargedwhen the auxiliary load requires less energy than available excessenergy from the welding power supply unit.
 7. The auxiliary powerconversion device of claim 1, wherein the input-to-output isolationcircuit comprises a high frequency ferrite-based transformer.
 8. Theauxiliary power conversion device of claim 1, wherein the auxiliarypower conversion device comprises a portable enclosure that houses theinput power converter, input-to-output isolation circuit, and the outputpower converter, and connects to the auxiliary load.
 9. The auxiliarypower conversion device of claim 8, wherein the portable enclosure isseparate from the welding power supply unit.
 10. The auxiliary powerconversion device of claim 1, wherein the auxiliary power conversiondevice comprises a portable enclosure that is configured to attachbetween the welding power supply unit and a welding process.
 11. Theauxiliary power conversion device of claim 10, wherein the portableenclosure is separate from the welding power supply unit.
 12. Theauxiliary power conversion device of claim 10, wherein the portableenclosure is a wire feeder.
 13. The auxiliary power conversion device ofclaim 1, wherein the input-to-output isolation circuit comprises a highfrequency transformer and a high frequency inverter.
 14. The auxiliarypower conversion device of claim 1, wherein the input-to-outputisolation circuit comprises a coupled magnetic device.
 15. A weldingsystem comprising: a welding power supply unit; an electrode assemblycomprising an electrode cable configured to connect to the welding powersupply unit; an auxiliary assembly comprising an auxiliary cable and anauxiliary clamp configured to be connected to a workpiece; and anauxiliary power conversion device configured to connect to the electrodeassembly and the auxiliary assembly, to create alternating current (AC)power from an arc potential created by the welding power supply unit, toconvert the AC power to a desired frequency and a desired waveform forone or more auxiliary devices connected to the auxiliary assembly, andto supply the converted AC power to the one or more auxiliary devices.16. The welding system of claim 15, wherein the auxiliary powerconversion device is configured to communicatively couple the one ormore auxiliary devices with the arc potential.
 17. The welding system ofclaim 15, wherein the auxiliary power conversion device comprises aportable enclosure separate from the welding power supply unit.
 18. Thewelding system of claim 15, wherein the auxiliary power conversiondevice is located in a portable wire feeder.
 19. The welding system ofclaim 15, wherein the auxiliary power conversion device attaches to theelectrode cable via the auxiliary cable.
 20. The welding system of claim15, comprising a lead assembly comprising a lead cable and a work leadclamp configured to be connected to a workpiece.